Cannot Email Multiple Contacts in Sage 300
Summary
Email to multiple contacts fails, with or without UseCommaAsEmailAddressSeparator = Yes parameter set in a4w.ini file
Resolution
Along with UseCommaAsEmailAddressSeparator=Yes parameter, ensure the contact in multiple contacts has Contact consents to receive emails checked to on.
In Common Services, Multiple Contacts, select Contact, and ensure Contact consents to receive emails is checked.